Search

[Objective] Most gas combustion devices used in university laboratories are custom-built. Given the widespread use of mixed gases, both the devices and experiments pose significant risks. Inadequate consideration of safety during the design, manufacture, and operation of these devices increases the likelihood of explosion accidents, which can result in severe injuries and property damage. Therefore, engineering control measures should be implemented to reduce the risk of such accidents. [Methods] This paper proposes using the Le Chatelier formula to estimate the explosion limits of combustible mixed gases. It emphasizes creating a flammability diagram for combustible gas--inert gas--oxygen mixtures and presents the combustion and explosion characteristics of mixed gases with varying volume fractions under standard temperature and pressure conditions. This approach offers a quantitative method for mitigating explosion risks by incorporating inert gases into combustion experiments. Additionally, the paper classifies combustion devices into two categories: normal pressure burners and deflagration/detonation devices. [Results] A comparison of the two types of devices reveals that deflagration/detonation devices pose a higher safety risk. When preparing and handling combustible mixed gases in these devices, special attention should be given to the impact parts of the device during gas flow, as these components are more prone to abnormal temperature increases. This paper estimates the temperature after adiabatic compression of commonly used combustible gases, such as methane and oxygen, and suggests that adiabatic compression in the negative pressure state of impact parts may lead to accidental combustion and explosion. Moreover, the explosion hazards associated with gas combustion devices are discussed from several perspectives, including the explosion temperatures and pressures of commonly used combustible gases in the laboratory and the effects of explosion overpressure on human health. [Conclusions] From the standpoint of inherent safety, the following recommendations are proposed: 1 Relatively safe combustible gases should be chosen for experimental schemes whenever possible. Inert gases should be selected based on their inerting capacity. Normal-pressure burners should be chosen, or the volume of the combustion chamber and gas mixing tank in deflagration/ detonation devices should be minimized as much as feasible. 2 Experimental devices should be equipped with appropriate valves, impact parts should be minimized, and a status monitoring and control system should be used to promptly address abnormal situations. Additionally, filters, flame arresters, pressure relief valves, and other necessary safety features should be installed. 3 The laboratory environment must meet the requirements for combustion experiments. Devices with explosion potential should be isolated. The room should be equipped with combustible gas detection and alarm systems, adequate ventilation, explosion-proof electrical equipment, and complete emergency supplies. 4 The configuration and proper use of personal protective equipment should be standardized. By implementing a comprehensive set of explosion prevention and control measures, accidents can be prevented, their progression can be managed, their consequences can be mitigated, and the overall safety of combustion experiments can be improved. [ABSTRACT FROM AUTHOR]

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to reduce the repeated work intensity of drilling personnel and the risks faced by high-risk environments during oilfield exploitation, an intelligent manipulator is introduced into the drilling platform, and a dynamic target tracking control method of the manipulator based on deep reinforcement learning is proposed in this paper. In this paper The digital twin of the manipulator is constructed in the virtual drilling simulation environment, and multi-agent parallel training is carried out using the machine learning agents(ML-Agents) framework and proximal policy optimization(PPO) algorithm. The ideal training algorithm model is deployed to the virtual manipulator on the virtual drilling platform, and the virtual and real manipulator can track the dynamic target synchronously through serial communication. The experimental results indicate that synchronous tracking of dynamic targets with virtual and real robotic arms is feasible and accurate, providing a new approach for the digital twin application in the oil and gas industry. [ABSTRACT FROM AUTHOR]

[Objective] Recently, underground space disasters have occurred with increasing frequency, highlighting the urgent need for a comprehensive, multidimensional support system for emergency communication. A key task in emergency communication for underground spaces is the rapid reorganization of communication networks to relay disaster information in real time. Unmanned aerial vehicles(UAVs), with their flexible deployment, unmanned operation, and all-terrain mobility, can play a vital role in emergency rescue efforts. In the event of disasters such as fires, collapses, or floods, UAVs can quickly access affected areas and establish stable ad-hoc networks using their onboard communication devices. UAVs can promptly transmit the collected disaster information back to the rescue center, thereby enhancing the efficiency of rescue operations. However, while extensive research has been conducted on UAV applications in low-altitude areas, further development is necessary for their use in underground spaces. Particularly, there is a lack of research on experimental platforms that integrate scientific research and teaching. This gap has resulted in a disconnect between the educational content and real-world scenarios. Therefore, establishing a scenario-based teaching and practice platform for emergency communication networks in underground spaces is essential. By enhancing practical teaching content, we can effectively guide students in learning modern emergency communication network technologies, ensuring a strong connection between theoretical instruction and real-world applications. [Methods] In this paper, we employ hypergraph theory to abstract the rapidly changing network topology into a dynamically evolving hypergraph, modeling the evolution of interference relations through the insertion and deletion of superedges. Specifically, we reformulate the dynamic channel selection problem in UAV communication networks as a hypergraph coloring problem. To adapt to the dynamic network topology, we leverage reinforcement learning theory to enhance the traditional hypergraph coloring algorithm and develop a dynamic hypergraph coloring algorithm. Additionally, when the topology of the UAV communication network changes, the traditional greedy algorithm requires recalculation at each time slot, whereas the Q-learning algorithm can quickly converge based on prior learning. Building on this discussion, we propose a dynamic channel selection algorithm based on the Q-learning framework, which can adjust the learning rate parameters according to the rate of topological changes. [Results] To validate the effectiveness of our proposed algorithm, we conduct extensive simulation experiments to observe how the proportion of link conflicts in the network changes with varying algorithm iterations and UAV flight speeds. Additionally, we analyze the changes in average throughput across different network sizes, comparing the Q-learning algorithm to the greedy algorithm. The simulation results demonstrate that our algorithm can dynamically adjust the learning rate parameters based on the topological change rate of the UAV communication networks, achieving an optimal trade-off between algorithm performance and convergence speed. And the network performance of this algorithm is better than that of the greedy algorithm. [Conclusions] In conclusion, we utilize hypergraph theory to design an adaptive channel selection algorithm based on the Q-learning framework and establish a simulation experiment platform using ns-3 simulation software. Specifically, we employ the ns-3 platform to create a network simulation experiment for an underground space emergency scenario, helping students apply their theoretical knowledge of communication networks to practical engineering contexts. This work lays a solid foundation for developing a simulation teaching platform for UAV emergency communication networks within the interdisciplinary integration of electronic information science and emergency management. [ABSTRACT FROM AUTHOR]

[Objective] Clearance between motion pairs is commonly observed in mechanisms due to manufacturing errors in components, assembly requirements, and wear of the mechanisms. When the mechanism operates at high speeds with large loads and small cross-sectional areas, components are susceptible to elastic deformation. This elastic deformation, combined with the clearance in motion pairs, significantly restricts the motion accuracy of the entire mechanism, leading to chaotic behavior and ultimately reducing its stability and reliability. Therefore, it is essential to investigate the influence of the coupling effect between the clearance of the motion pair and the flexible component on the motion state of the mechanism. [Methods] This paper proposes a chaos identification method for a rigid-flexible coupling experimental teaching platform with revolute clearance joints. First, a revolute clearance joint model was established based on the three-state model of "contact-separation-collision." In addition, a flexible beam element model was created using the absolute node coordinate method. Following this, a dynamic model of the rigid-flexible coupling six-link experimental platform with revolute clearance joints was established using the Lagrange multiplier method. Finally, both qualitative and quantitative identifications of chaotic phenomena in the six-link experimental platform were conducted using phase diagrams, Poincaré maps, and maximum Lyapunov exponents. The nonlinear characteristics of the rigid experimental platform with clearance and the rigid-flexible coupling experimental platform with clearance were compared and analyzed. Additionally, the effects of different clearance values, driving speeds, and friction coefficients on the nonlinear characteristics of the experimental teaching platform were studied. [Results] The results obtained using methods such as phase diagrams, Poincaré maps, and maximum Lyapunov exponents indicate that compared with the rigid experimental teaching platform mechanism with revolute clearance, the vibration frequency of the rigid-flexible coupling experimental teaching platform mechanism with revolute clearance is higher, leading to reduced stability and more pronounced chaotic phenomena. The chaotic behavior at the clearance of the revolute pair intensifies with an increase in clearance size and driving speed, whereas it weakens as the friction coefficient increases. [Conclusions] The coupling effect between the clearance of the motion pair and the flexibility of the component reduces the stability of the mechanism, leading to the emergence of chaos. The chaos identification method based on the experimental teaching of rigid-flexible coupling with revolute clearance proposed in this article can effectively distinguish the motion states of the mechanism. This method provides a systematic and comprehensive theoretical foundation for the study of nonlinear dynamics in high-precision, high-performance multilink mechanisms. This not only enhances students' ability to analyze and practice the nonlinear characteristics of mechanisms but also increases the diversity, intuitiveness, and engagement of the teaching process, ultimately improving the quality of education. [ABSTRACT FROM AUTHOR]

[Objective] With the rapid development of the Internet of Things and network communication technology, cryptography has advanced significantly. Current hash function software can process multiple messages in parallel, making hash functions widely applicable for file tamper-proofing and software installation verification on mobile phones. However, existing hash function software often suffers from low speed and throughput, which hinders the processing of large-scale data in Internet of Things applications. Algorithm hardware can efficiently process large-scale data through algorithm adaptation and path optimization. Consequently, this experiment designs a hardware circuit for the SM3 cryptographic hash algorithm using Verilog hardware description language (HDL) to enhance the speed and throughput of the algorithm, thereby addressing the demand for high-speed hashing algorithms in Internet of Things applications. [Methods] This paper examines the speed and throughput of hash algorithm hardware using various optimization technologies and loop expansion methods. By comparing different techniques, the experiment presents an optimized SM3 hash algorithm. The Verilog HDL code implements the hardware circuit for the SM3 cryptographic hash algorithm, which is simulated using ModelSim by Mentor Graphics Corporation. According to the simulation results from the static sequence, the experiment identifies the critical path of the hardware. Leveraging this static sequence analysis, the study employs loop expansion technology and the conditional-select adder (CSA) to enhance processing speed and shorten the critical path. Furthermore, the FPGA is used to implement the hardware system experimentally and conduct a sequence test to evaluate throughput. According to the experimental results, the hardware incorporates the two-in-one structure loop expansion technology, which reduces two-step calculations to one step. As a result, the number of iterations for compression decreases from 64 to 32. This structure significantly improves calculation efficiency and reduces processing time. Additionally, this experiment proposes a CSA tree topology in the critical path to minimize logic delay without compromising accuracy. [Results] The experimental results for the hardware circuit of the SM3 cryptographic hash algorithm indicated that: 1) The initial and optimized delays were 6.006 ns and 5.525 ns, respectively, according to the simulation results from ModelSim. This represents a reduction in delay of 0.481 ns for the hardware circuit. 2) The proposed CSA tree topology in the optimized hardware system reduced logic delay by 8.01% experimentally, further enhancing overall calculation speed and efficiency. 3) The two-in-one loop expansion technology implemented in the optimized hardware system increased throughput from 822.4 Mb/s to 1 069.5 Mb/s, achieving an improvement rate of 30%. [Conclusions] By incorporating the two-in-one structure loop expansion technology and the CSA tree topology, the hardware circuit for the SM3 cryptographic hash algorithm in this experiment shortens the critical path and reduces logic delay. As a result, calculation speed and efficiency are greatly enhanced. The presented hardware circuit achieves high speed and throughput, enabling the processing of large-scale data without time expansion. Overall, this study significantly contributes to the processing of large-scale data in the Internet of Things and network communication technology. [ABSTRACT FROM AUTHOR]

[Objective] Gabion is widely used in slope stabilization, revetment engineering, subgrade reinforcement, and other applications. However, its use in tunnel lining remains underexplored. Owing to its unique multiporosity, which provides excellent deformation capacity and notable bearing strength, gabion shows promising potential for managing the notable deformations and high ground stresses encountered in tunnel surrounding rock. Therefore, studying the static mechanical behavior of tunnel lining components made with gabion is of practical importance. [Methods] This paper presents a simplified molding technique for gabion components and a custom-designed test loading apparatus. Additionally, a numerical modeling methodology specifically tailored for gabion components in tunnel lining is introduced based on discrete element calculations. Next, a comparative analysis is conducted to examine the influence of two key parameters--the strength of the gabion mesh and the effective modulus of the stone filling--on the variation in static mechanical characteristics of tunnel lining components constructed with gabion. This study provides valuable insights into the performance of gabion-based tunnel linings. [Results] 1) The failure of the gabion component in tunnel lining mainly occurs through instability, with only minor cases of wire breakage and stone-filling fracture. Throughout the loading process, the load-displacement curve of the component exhibits notable fluctuations driven by the ongoing interaction between the internal stone filling and the gabion mesh. The overall load-displacement curve increases and then decreases. Despite considerable deformation, the component maintains a high bearing capacity at the end of loading. 2) The tensile strength of the gabion mesh has little effect on the deformation modulus during the initial deformation stage under static load but has more impact on the peak load. The higher the tensile strength of the gabion mesh, the greater the displacement and peak strength at peak load. Under varying tensile strength conditions, the differences in peak load displacement and peak strength reached 28.9% and 25.2%, respectively, because when the tensile strength of the gabion mesh is higher, the component is more resistant to failure, allowing a more effective interaction between the stone filling and the gabion mesh. 3) Compared with the tensile strength of the gabion mesh, the effective modulus of stone filling has a pronounced impact on the component performance. As the effective modulus of the stone filling increases, the postpeak decline in the load-displacement curve becomes more prominent. During the loading process, the energy consumption of the component, peak loading strength, and effective modulus of the stone filling exhibit a distinct piecewise relationship, characterized by an initial increase followed by stabilization. [Conclusions] This experiment provides clear guidance for students conducting static loading mechanical model tests on gabion-constructed tunnel lining components, enhancing the effectiveness of experimental teaching. [ABSTRACT FROM AUTHOR]

[Objective] As automated drilling technologies become more prevalent, the demand for data communication while drilling has significantly risen, leading to increased requirements for downhole data communication systems. Currently, pressure wave data communication, which utilizes mud as the transmission medium, is the leading technology in these systems. The core component of these systems is the mud pressure wave generator (MPWG), which produces pressure wave signals with specific phases by adjusting the flow area of the mud through the operation of a rotary valve. Therefore, phase modulation of pressure wave signals and the control method of the rotary valve are critical technologies for the MPWG. Unlike conventional phase modulation methods, the phase of the pressure wave signal cannot change abruptly. Additionally, the drilling mud scours the rotary valve, introducing torque disturbances that make it challenging for the valve to accurately reach the desired position, ultimately reducing the quality of the pressure wave signal. [Methods] To tackle the issues of phase modulation of pressure wave signals and rotary valve position control, this paper proposes a lower sideband constant envelope smooth phase modulation method for pressure signals. Under the condition of maintaining a constant pressure wave amplitude, we introduce a parameter called the adjustable symbol transition time ratio (ASTTR) to achieve smooth phase modulation, along with a lower-sideband modulation method designed to reduce power consumption. Following this, a rotary valve position control system for the MPWG is designed. The speed and position controllers are designed using the active disturbance rejection control algorithm to ensure accurate tracking of the rotary valve position setpoint, even in the presence of external disturbance torques. Finally, a testing device is developed that integrates torque loading, parameter tuning, and data management functions to validate the proposed methods. This device allows for teaching experiments and testing of the MPWG to be conducted without the need for hydraulic circulation. [Results] Two experiments were conducted using the testing device. In Experiment 1, the valve control performance was evaluated under constant and fluctuating torque disturbances. The transmitted symbols of the MPWG are {0, 1, 0, 0, 1, 1}, the symbol period is 0.333 s, and the carrier frequency is 18π rad/s. When the ASTTR is set to 1, the position control errors under constant and fluctuating torque disturbances are 0.039 rad and 0.040 rad, respectively. When the ASTTR is set to 0.5, the position control errors are 0.059 rad and 0.058 rad under constant and fluctuating torque disturbances, respectively. The test results indicated that smooth phase modulation was successfully achieved. Moreover, a larger ASTTR, which facilitates smoother changes in the position setpoint, corresponds to smaller position tracking errors. Additionally, the tracking errors for the same position setpoint under different torque disturbances are similar, indicating that the control system performs effectively in the presence of torque disturbances. In Experiment 2, the power consumption of conventional double-sideband modulation is compared to that of the proposed lower-sideband modulation. The average power consumption for double-sideband modulation was 35.2 W, whereas the average power consumption for the proposed method is 32.6 W, demonstrating a 7.4% reduction in power consumption. [Conclusions] The experimental results demonstrate that the proposed method effectively achieves smooth phase modulation of pressure wave signals and disturbance rejection control of the rotary valve. Furthermore, the proposed method and experimental device exhibit multidisciplinary integration characteristics, enhancing students' ability to address real-world complex engineering problems. [ABSTRACT FROM AUTHOR]

[Objective] The deposition of Cl-containing harmful salts on the surface of service materials critically influences their corrosion process. The Qinshan Nuclear Power Station, located near the sea, has encountered corrosion issues due to the deposition of these harmful salts. Although researchers have conducted numerous in-depth studies on the corrosion behavior and mechanisms of materials in nuclear power plants, only limited literature addresses the deposition patterns of harmful salts on the surfaces of nuclear-grade materials. [Methods] A field environmental investigation was conducted to understand nuclear material corrosion in salty environments, and then a harmful salt solution for salt spray deposition experiments was formulated based on the investigation results following the ASTM standard. To investigate the deposition patterns of harmful salts on the surface of spent fuel storage canister materials, this solution was used for salt spray deposition on nuclear-grade materials. Tests were conducted at 90 °C to simulate the coastal service environment of the Qinshan Nuclear Power Station. [Results] The analysis of seawater composition revealed that the seawater near the Qinshan Nuclear Power Station is diluted by freshwater, as it is located near the Yangtze River estuary. Despite this dilution, a comparison with the global average sodium content of seawater indicated that the seawater near the Qinshan Nuclear Power Station retains the typical characteristics of normal seawater. The design results for the harmful salt solution indicated that, based on the total chloride content of substitute ocean water according to the ASTM D1141-98 standard (2021 edition), the concentration of each compound in the seawater near the Qinshan Nuclear Power Station must be multiplied by 4.075 26 for amplification. This adjustment allows the formulation of a harmful salt simulation solution for salt spray deposition that complies with ASTM standards. The experimental results of harmful salt deposition on the surface of nuclear-grade material at 90 °C indicated the following: By setting the sedimentation rate of the salt spray at 1.75 mL/(h·80 cm2) and establishing a single salt spray period as "1 min of salt spray followed by 15 min of standing," one salt spray period was necessary for the average harmful salt concentration on the surface of the sample to reach 0.1 g/m² (using thin slice samples measuring 100 mmx100 mmx 0.1 mm). To achieve a concentration of 1.0 g/m², 12 salt spray cycles were required (using flat samples measuring 50 mmx25 mmx2 mm). Finally, 112 salt spray cycles were needed to reach a concentration of 10.0 g/m² (also using flat samples measuring 50 mmx25 mmx2 mm). [Conclusions] The seawater near the Qinshan Nuclear Power Station retains the characteristics of normal seawater. This paper proposes a laboratory design concept and serves as a reference for evaluating the service life and performance of materials used in nuclear power plants operating in actual service environments. [ABSTRACT FROM AUTHOR]

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)